1) Field of the Invention
The present invention relates to a paper-leaves separating/supplying method and apparatus suitable for use in a paper-leaves division system and properly employable in separating a plurality of paper leaves such as mail, deposited together in a bundle, to convey them one by one to a partitioning section.
2) Description of the Related Art
In the recent years, a mail division apparatus, which includes a recognizing function for reading a bar-code attached to mail or a character recognizing function for reading destination information such as a postal code to divide the mail automatically on the basis of these destination information, has been put in practical use. Such a paper-leaves division apparatus, which is made to handle mail or the like (which will be referred to hereinafter to xe2x80x9cpaper leaves (sheets)xe2x80x9d), has been required to meet requirements such as space-saving, labor-saving, cost reduction and fast operation (speed-up). A means to realize the fast operation of these requirements has been required to eliminate the occurrence of troubles such as overlap transportation in the middle of the conveyance and further to accomplish the conveyance and the partitioning operation promptly and accurately.
In general, such a type of paper-leaves division apparatus is designed to separate a plurality of paper leaves to be divided, deposited together in a bundle in a stand-up condition, from each other in a separating/supplying section and subsequently send them successively toward the downstream side. Accordingly, if the separating/supplying section cannot achieve the separation of the paper leaves properly and promptly, then this has great influence on the subsequent reading of the address information and the accuracy and speed of the partitioning operation. In addition, the proper and prompt separation in the separating/supplying section provides an effect to enhance the handling ability of a large number of paper leaves. Accordingly, for achieving the fast separation of the paper leaves, a simple-structure paper-leaves arrival detecting means is provided at a paper-leaves feeding (transferring) position to detect the arrival of the paper leaves.
Meanwhile, the fast and continuous conveyance of a large quantity of paper leaves may cause slight operational discordance in the paper-leaves conveyance path to develop instability factors so that the interval between one paper leaf and the subsequent another paper leaf lengthens and shortens, thus leading to the occurrence of overlap transportation so that difficulty is experienced in correctly conducting the partitioning operation of the paper leaves to be done after the conveyance. One of the instability factors is that, in a case in which paper leaves are fed in a collectively set condition and in a stand-up condition, if a paper leaf (which will be referred to hereinafter as a xe2x80x9csucceeding paper leafxe2x80x9d) traveling afterward falls down to lean against a paper leaf (which will be referred to hereinafter as a xe2x80x9cpreceding paper leafxe2x80x9d) running ahead of the succeeding paper leaf, the weight of the succeeding paper leaf is placed on the preceding paper leaf, thus generating a contact pressure between the preceding paper leaf and the succeeding paper leaf. In addition, this contact pressure develops a load at the feed of the preceding paper leaf to hinder the smooth feeding operation, or the succeeding paper leaf is dragged by the preceding paper leaf to fall into an irregular condition so that the further feeding of the succeeding paper leaf can be conducted in an unstable state. Still additionally, the sucking paper leaf is dragged by the preceding paper leaf to be sent in a state where two pieces overlap with each other, that is, the so-called overlap transportation occurs. Accordingly, in order to solve these problems, there is a need to reduce the contact pressure between the preceding paper leaf and the succeeding paper leaf by as much as possible in feeding (letting out) the preceding paper leaf.
Furthermore, a key to fast and continuous conveyance of a large quantity of paper leaves is that the system accurately recognizes the arrival of paper leaves at a separating/feeding belt surface and appropriately feeds the paper leaves successively or continuously. A conventional mechanical paper-leaves arrival detecting means is placed immediately before the separation/supply section and is designed to make a decision on the arrival in a manner that a paper leaf is brought into point (or line) contact with the paper-leaves arrival detecting means. In addition, this paper-leaves arrival detecting means can fail to detect the arrival of the paper leaves depending upon situations such as the weight, thickness, surface roughness or supplying posture of the paper leaves, which interferes with the prompt separation/supply. In this respect, the conventional paper-leaves arrival detecting means does not fulfill its purpose sufficiently.
The present invention has been developed with a view to eliminating these problems, and it is therefore an object of the invention to provide a paper-leaves separating/supplying method and apparatus, capable of, in feeding paper leaves, reducing the contact pressure occurring between the preceding paper leaf and the succeeding paper leaf to certainly feed the paper leaves one by one for accomplishing the conveyance of the paper leaves with high accuracy without exerting adverse influence on the succeeding paper leaf, such as overlap transportation.
Another object of the invention is to a paper-leaves separating/supplying method and apparatus capable of precisely detecting the paper leaves conveyed up to a paper-leaves feeding position to successively feed the paper leaves with accuracy.
A further object of the present invention is to accurately accomplish the conveyance of paper leaves without troubles such as overlap transportation.
For these purposes, in accordance with a first aspect of the present invention, there is provided a paper-leaves separating/supplying method comprising the steps of placing a belt surface of a separating/supplying belt in a state substantially perpendicular to a conveying direction of a plurality of paper leaves set together and conveyed in a stand-up condition or in a state inclined toward the paper leaves conveyed, taking up the paper leaves, conveyed up to a position at which the paper leaves come into contact with the belt surface, by vacuum suction on the belt surface side so that the paper leaf adheres onto the belt surface, and feeding the one paper leaf taken up toward the downstream side in accordance with the rotary motion of the separating/supplying belt.
Thus, the preceding paper leaf coming previously into contact with the belt surface is attracted and held on the separating/supplying belt in a state parallel with or inclined toward the succeeding paper leaf, and then fed in accordance with the rotary motion of the separating/supplying belt. Accordingly, the weight of the succeeding paper leaf hardly fall on the preceding paper leaf when the preceding paper leaf is fed to the downstream side, thus minimizing the contact pressure between the preceding paper leaf and the succeeding paper leaf to achieve smooth feeding thereof. In addition, it is possible to prevent the succeeding paper leaf from being dragged by the preceding paper leaf to be disarranged in posture, which assures that the paper leaves are conveyed with accuracy without the occurrence of troubles.
Furthermore, in accordance with a second aspect of the present invention, there is provided a paper-leaves separating/supplying apparatus comprising a rotary separating/supplying belt, vacuum suction means for taking up a plurality of paper leaves, set together and conveyed in a stand-up condition, through the use of vacuum suction so that they are attached onto a belt surface of the separating/supplying belt, and separating/supplying means for feeding the paper leaves, attached onto the belt surface by the vacuum suction, one by one to the downstream side in accordance with the rotary motion of the separating/supplying belt, wherein the belt surface of the separating/supplying belt is placed in a state substantially perpendicular to a conveying direction of the paper leaves or in a state inclined toward the paper leaves. With this construction, the paper leaf (preceding paper leaf) coming previously into contact with the belt surface is sucked to be held on the separating/supplying belt in a state parallel to the paper leaf (succeeding paper leaf) coming afterward or in a state inclined toward the succeeding paper leaf, and fed by the rotary motion of the separating/supplying belt. Accordingly, the weight of the succeeding paper leaf hardly fall on the preceding paper leaf when the preceding paper leaf is fed to the downstream side; therefore, this minimizes the contact pressure between the preceding paper leaf and the succeeding paper leaf to enable the smooth feeding of the paper leaves. In addition, it is possible to prevent the succeeding paper leaf from being dragged together by the preceding paper leaf to be disarranged in posture, which assures that the paper leaves is conveyed with accuracy without the occurrence of troubles.
Still furthermore, in accordance with a third aspect of the present invention, there is provided a paper-leaves separating/supplying method comprising the steps of vacuum-sucking a plurality of paper leaves, set together and conveyed in a stand-up condition, one by one toward a belt surface of a separating/supplying belt of separating/supplying means, bringing a lower end portion of the paper leaf, conveyed to the belt surface, into contact with an auxiliary contact surface placed under the separating/supplying means for feeding the paper leaves to the downstream side in accordance with rotary motion of the separating/supplying belt, attracting the lower end portion of the paper leaf onto the auxiliary contact surface through the use of auxiliary vacuum suction means, and measuring a negative pressure of the auxiliary vacuum suction means for detecting that the paper leaf arrives at the belt surface.
With this method, even though a paper-leaves arrival sensor does not detects that the paper leaf has arrived at the position of the belt surface because it shifts during conveyance, when the paper leaf is brought into contact with the auxiliary contact surface and is attracted thereonto by vacuum suction, the negative pressure exceeds a predetermined value, so the arrival of the paper leaf is detectable on the basis of the measured negative pressure, which secures a continuous paper-leaves feeding operation by the separating/supplying means.
Moreover, in accordance with a fourth aspect of the present invention, there is provided a paper-leaves separating/supplying apparatus comprising separating/supplying means including a rotary separating/supplying belt and first vacuum suction means for vacuum-sucking each of a plurality of paper leaves, set together and conveyed in a stand-up condition, through a belt surface of the separating/supplying belt to suction-hold the paper leaf on the belt surface, with separating/supplying means feeding the paper leaves suction-held on the belt surface one by one to the downstream side in accordance with rotary motion of the separating/supplying belt, auxiliary separation means including an auxiliary contact surface placed under the separating/supplying means for receiving a lower end portion of the paper leaf transferred to the belt surface and second vacuum suction means for generating a vacuum suction force to attract the lower end portion of the paper leaf onto the auxiliary contact surface, a paper-leaves arrival detecting means for detecting the arrival of the paper leaf when the paper leaf is transferred to the belt surface, and negative pressure measuring means for measuring a negative pressure in the second vacuum suction means.
Also with this construction, even though a paper-leaves arrival sensor fails to detect that the paper leaf has arrived at the position of the belt surface because it shifts during conveyance, when the paper leaf is brought into contact with the auxiliary contact surface and is attracted thereonto by the second vacuum suction means, the negative pressure in the second vacuum suction means exceeds a specified value, so the arrival of the paper leaf is detectable on the basis of the measured negative pressure, which secures a continuous paper-leaves feeding operation by the separating/supplying means.
Still moreover, in accordance with a fifth aspect of the present invention, there is provided a paper-leaves separating/supplying method comprising the steps of vacuum-sucking a plurality of paper leaves, set together and conveyed up to a paper-leaves feeding position in a stand-up condition, one by one toward a belt surface of a separating/supplying belt of separating/supplying means, bringing a lower end portion of the paper leaf, transferred to the belt surface, into contact with an auxiliary contact surface placed under the separating/supplying means for feeding the paper leaves to the downstream side in accordance with rotary motion of the separating/supplying belt, attracting the lower end portion of the paper leaf onto the auxiliary contact surface through the use of auxiliary vacuum suction means, when the paper leaf is suction-attracted onto the auxiliary contact surface, making a central portion of the paper leaf protrude to the auxiliary contact surface side and making both sides of the paper leaf warp so that its horizontal cross section forms a generally arch-like configuration.
With this method, the preceding paper leaf is bent into an arch-like configuration so that its both end portions protrude toward the succeeding paper leaf, and at this time, this protrusion of both the end portions of the preceding paper leaf separates the succeeding paper leaf, conveyed in a state brought into contact with the preceding paper leaf, from the preceding paper leaf, thus preventing the overlap transportation of the paper leaves and securing regular conveyance thereof.
In addition, according to this paper-leaves separating/supplying method, air is supplied to the paper leaf, bent into the arch-like configuration, from the under to separate the succeeding paper leaf from the preceding paper leaf. Thus, in addition to the flipping or separation effect stemming from the protrusion of the preceding paper leaf, this air blowing can more certainly achieve the separation between the paper leaves, thus enabling more positively feeding the paper leaves one by one.
Furthermore, in accordance with a sixth aspect of the present invention, there is provided a paper-leaves separating/supplying apparatus comprising separating/supplying means including a rotary separating/supplying belt and first vacuum suction means for vacuum-sucking each of a plurality of paper leaves, set together and conveyed in a stand-up condition to a paper-leaves feeding position, through a belt surface of the separating/supplying belt to suction-hold the paper leaf on the belt surface, with separating/supplying means feeding the paper leaves suction-held on the belt surface one by one to the downstream side in accordance with rotary motion of the separating/supplying belt, and auxiliary separation means including an auxiliary contact surface placed under the separating/supplying means to confront a lower end portion of the paper leaf conveyed to the paper-leaves feeding position and second vacuum suction means for generating a vacuum suction force in the inside of the auxiliary contact surface to attract the lower end portion of the paper leaf onto the auxiliary contact surface, wherein the auxiliary contact surface has an irregular member whereby, when the paper leaf is attracted onto the auxiliary contact surface, a central portion of the paper leaf protrudes toward the auxiliary contact surface side and both end portions thereof protrude toward the succeeding paper leaf coming afterward so that a horizontal cross section of the paper leaf is formed into a generally arch-like configuration.
Likewise, with this construction, the preceding paper leaf is bent into an arch-like configuration so that its both end portions protrude toward the succeeding paper leaf, and at this time, this protrusion of both the end portions of the preceding paper leaf separates the succeeding paper leaf, conveyed in a state brought into contact with the preceding paper leaf, from the preceding paper leaf, thus preventing the overlap transportation of the paper leaves and securing regular conveyance thereof.
In addition, according to this paper-leaves separating/supplying apparatus, the auxiliary contact surface is disposed to make a predetermined angle between the auxiliary contact surface and the belt surface of the separating/supplying belt so that the paper leaf attracted onto the auxiliary contact surface is bent toward the succeeding paper leaf. Accordingly, the paper leaf bent into the arch-like configuration is further bent into a doglegged configuration to form a gap with respect to the succeeding paper leaf, thereby more positively securing the separation between the preceding paper leaf and the succeeding paper leaf.
Still additionally, the irregular member of the auxiliary contact surface is formed so that its lower end portion has a flat configuration. This structure makes a larger gap between the lowermost portion of the paper leaf attracted onto the auxiliary contact surface and the succeeding paper leaf, which enables more efficient separation of the preceding paper leaf from the succeeding paper leaf when air is supplied into the enlarged gap between the preceding paper leaf and the succeeding paper leaf.
Furthermore, in accordance with a sixth aspect of the present invention, there is provided a paper-leaves separating/supplying apparatus comprising separating/supplying means including a rotary separating/supplying belt and first vacuum suction means for vacuum-sucking each of a plurality of paper leaves, set together and conveyed in a stand-up condition to a paper-leaves feeding position, through a belt surface of the separating/supplying belt to suction-hold the paper leaf on the belt surface, with separating/supplying means feeding the paper leaves suction-held on the belt surface one by one to the downstream side in accordance with rotary motion of the separating/supplying belt, and auxiliary separation means including an auxiliary contact surface placed under the separating/supplying means to confront a lower end portion of the paper leaf conveyed to the paper-leaves feeding position, second vacuum suction means for generating a vacuum suction force in the inside of the auxiliary contact surface to attract the lower end portion of the paper leaf onto the auxiliary contact surface and an irregular member whereby, when the paper leaf is attracted onto the auxiliary contact surface, a central portion of the paper leaf protrudes toward the auxiliary contact surface side and both end portions thereof protrude toward the succeeding paper leaf coming afterward so that a horizontal cross section thereof is warped in a generally arch-like configuration, and air blowing means for supplying air between the preceding paper leaf and the succeeding paper leaf from under the paper leaves to make separation between the preceding paper leaf, attracted onto the auxiliary contact surface, and the succeeding paper leaf.
With this construction, the preceding paper leaf is bent into an arch-like configuration so that its both end portions protrude toward the succeeding paper leaf, and at this time, this protrusion of both the end portions of the preceding paper leaf separates the succeeding paper leaf, conveyed in a state brought into contact with the preceding paper leaf, from the preceding paper leaf. In addition, air is supplied between the preceding paper leaf and the succeeding paper leaf, thus achieving more positive separation between the preceding paper leaf and the succeeding paper leaf and securing regular conveyance thereof.
Moreover, the irregular member is made so that its lowermost portion corresponding to the lowermost portion of the paper leaf brought into contact with the auxiliary contact surface has a flat configuration. This structure makes a larger gap between the lowermost portion of the paper leaf attracted onto the auxiliary contact surface and the succeeding paper leaf, which enables more efficient separation of the preceding paper leaf from the succeeding paper leaf when air is supplied into the enlarged gap between the preceding paper leaf and the succeeding paper leaf.